= 
324 oy COMPOSIT " MICROPUS 
ceous. Receptacle naked. Tall herbs. 
82 1nuLA_ Heads heterogamous, radiate, with all the flowers fertile: pap- 
pus of capillary bristles. a 
SUBTRIBE IV ADENOCAULE# Bracts of the involucre herbaceous, 
few, in a'single series. Receptacle not chaffy. Heads few-flowered : 
both pistillate and hermaphrodite sterile flowers with similar di- 
lated tubular corollas, the former rather fewer and with enlarged 
exsert2d achenes 
38 Adenocaulon Achenes club-shaped and several times longer than the 
involucre, beset with some stipitate glands: pappus none. 
SUBTRIBE V DIMERESEX Bracts of the involucre herbaceous, 
few, in a single series. Receptacle not chaffy. Flowers few, her- 
maphrodite, fertile.. Pappus of rather few bristles. 
34 Dimeresia Heads 2-flowered: involucre of 2 slightly united bracts, — 
each almost enclosing a flower: pappus of 20 slightly united bristles 
that are early deciduous. ) 
Subtribe 1 Filaginex Fenzl Fl. i 729. Heads heterogamous, 
mostly androgynous, discoid. Involucre of few scarious or firmer 
_ bracts Receptacle chaffy, a. chaff or involucral bract enclosing or 
sudtending each pistillate flower or achene. Corolla of the pistillate 
flowers a filiform tube, shorter than the style; of the hermaphrodite 
commonly sterile flowers regularly 4-tonthed; their anthers sometimes 
only acutely sagittate or awriculate at base, and the short style-bran- 
ches or undivided stule not truncate. Achenes mostly smooth and 
even, small and seed-like, the very thin periearp destitute of nerves 
or other markings. 
25 MICROPUS Gaertn. Fr. t. 164. 
Low floccose-woolly annuals with entire leaves and small 
heads of inconspicuous flowers in sessile clusters. Heads discoid, 
several-floweted ; the pistillate flowers with filiform corolla forming 
a single series, each wholly enclosed in a conduplicate infolded 
and laterally compressed very gibbous chaff or scale, which be- 
comes firm-coriaceous or cartilaginous in fruit, and falls at ma- 
turity with the completely enclosed achene, inclined at length to 
dehisce into two valves; the bermaphrodite but sterile flowers 
with 4—5-toothed tubular corolla few and naked in the centre. 
Involucre of few scarious bracts. Receptacle small and short. 
Achenes obovate and gibbous laterally compressed, smooth, its 
apex lateral. Pappus wanting. 3 
M. Californicus F. & M. Ind. sem. Petrop 1835, 42. Stems slender, 
4-16 inches high, loosely white-woolly, sine or sparingly branched above, 
leafy to the top: leaves linear-oblong to oblong-lanceolate, entire, 6-8 lines 
long, densely tomentose with a fine somewhat silky white wool, the largest _ 
near the centre of the stem: headsin lateral and terminal clusters which 
are inclined to be spicate: fructiferous scales very woolly, under the wool. 
smooth, half-obcordate, with a suberect beak terminating in a somewhat 
dilated scarious apex. Common on dry open hillsides, southwestern Ore- 
